Daños en rodamientos

Handling damage

Excessive preload
or overload

Excessive end play

Tapered Roller Bearing Damage Analysis
Roller spaced nicking —
Raised metal on races from
contact with roller edges.

Rapid and deep spalling
caused by unusually high
stresses. Full race width
fatigue spalling is caused by
heavy loads creating a thin
lubricant film and possible
elevated temperatures.Scalloping — Uneven
localized wear resulting from
excessive end play.

The most common types of bearing damage that may result in a
reduction of bearing or application life are often caused by:
•
•
•
•

Fatigue spalling

insufficient maintenance practices
mishandling
improper installation and adjustment practices
inadequate lubrication

The following offers a quick reference to thecommon causes of
bearing damage.

Cage pocket wear — Heavy
contact between the rollers
and cage pocket surfaces
caused by bearing operating
too loosely.

Roller nicking/denting —
Rough handling or
installation damage.

Inadequate
lubrication*
Total bearing lock-up —
Rollers skew, slide sideways
and lock-up bearing.

WARNING!
Never spin a bearing with compressed air. The force of thecompressed air may cause the rollers to be expelled with
great velocity, creating a risk of serious bodily harm.

Inclusion origin — Spalling
from oxides or other hard
inclusions in bearing steel.

Roller end scoring — Metalto-metal contact from
breakdown of lubricant film.

Geometric stress
concentration — Spalling
from misalignment,
deflections or heavy loading.

Proper bearingmaintenance and handling practices are
critical. Failure to follow installation instructions and
failure to maintain proper lubrication can result in
equipment failure, creating a risk of serious bodily harm.
Cup-face denting — Indentations
from hardened driver.

If a hammer and mild steel bar are used for bearing removal,
fragments from the hammer, bar or the bearing can be
released withsufficient velocity to create a risk of serious
bodily injury including damage to your eyes.

Cone large rib face scoring —
“Welding” and heat damage
from metal-to-metal contact.
Cone large rib face
deformation — Metal flow
from excessive heat generation.

* Excessive preload can cause
damage similar to inadequate
lubrication damage.
Timken® is the registered trademark of
The TimkenCompany
www.timken.com
©2003 The Timken Company
Printed in USA
1M 08-05-07 Order No. 6347

THE TIMKEN COMPANY

Point surface origin —
Spalling from debris or raised
metal exceeding the lubricant
film thickness.

Foreign material

Abrasive wear — Fine abrasive
particle contamination.

High spots in
cup seats

Localized spalling on the cup
race from stress riser created
bysplit housing pinch point.

Corrosion / etching

Etching — Rusting with
pitting and corrosion from
moisture/water exposure.

Improper fit

Electric current

Peeling

Micro-spalling due to thin
lubricant film from high loads/low
RPM or elevated temperatures.
Cone bore damage —
Fractured cone due to out-ofround or oversized shaft.
Electric arc pitting — Small
burns created by arcsfrom
improper electric grounding
while the bearing is stationary.

Bruising — Debris from other
fatigued parts, inadequate
sealing or poor maintenance.

Staining — Surface stain with
no significant corrosion from
moisture exposure.

Cage damage

False brinelling

Cup spinning — Loose cup fit
in a rotating wheel hub.

Misalignment

Grooving — Large particle
contaminationimbedding
into soft cage material.

Cage Deformation —
Improperly installed or
dropped bearing.

Fluting —
Series of small
axial burns caused by electric
current passing through the
bearing while it is rotating.

Line spalling — Roller-spaced
spalling from bearings
operating after etching damage.

Irregular roller path from
deflection, inaccurate machining
or wear of bearing...